From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH net] net: sctp: inherit auth_capable on INIT collisions Date: Fri, 18 Jul 2014 17:59:58 -0400 Message-ID: <53C998DE.2030805@gmail.com> References: <1405620319-2021-1-git-send-email-dborkman@redhat.com> <53C93157.1050002@gmail.com> <53C972BE.5090700@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, jgunthorpe@obsidianresearch.com, netdev@vger.kernel.org, linux-sctp@vger.kernel.org To: Daniel Borkmann Return-path: Received: from mail-qg0-f47.google.com ([209.85.192.47]:42457 "EHLO mail-qg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752348AbaGRWAC (ORCPT ); Fri, 18 Jul 2014 18:00:02 -0400 In-Reply-To: <53C972BE.5090700@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On 07/18/2014 03:17 PM, Daniel Borkmann wrote: > On 07/18/2014 04:38 PM, Vlad Yasevich wrote: > ... >> Why is the original value of asoc->peer.auth_capable = 0? >> In case of collision, asoc is the old association that >> existed on the system. That association was created as part of >> sending the INIT. If it is processing a duplicate COOKIE-ECHO >> as you say, then it has already processed the INIT-ACK and >> should have determined that the peer is auth capable. >> >> Thus the capability of the new and the old associations should >> be same if we are in fact processing case B (collision). >> >> If not, then something else if wrong and my guess is that all >> other capabilities would be wrong too. > > I agree that they might likely also be flawed. > > Ok, let me dig further. So I think I know why case D ends up not authenticating the COOKIE-ACK. Most likely the reason is the following statement: repl = sctp_make_cookie_ack(new_asoc, chunk); Note that we use new_asoc, instead of current asoc. Not sure why case B is dumping core yet. -vlad